Articles | Volume 13, issue 3
https://doi.org/10.5194/esd-13-1289-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/esd-13-1289-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 Sep 2022
Research article |
| 06 Sep 2022
| 06 Sep 2022
Combining machine learning and SMILEs to classify, better understand, and project changes in ENSO events
The Ocean in the Earth System, Max Planck Institute for Meteorology, Hamburg, Germany
Cooperative Institute for Research in Environmental Sciences (CIRES) and Department of Atmospheric and Oceanic Sciences (ATOC), University of Colorado at Boulder, Boulder, CO 80309, USA
Thibault P. Tabarin
independent researcher: Boulder, CO 80303, USA
Sebastian Milinski
The Ocean in the Earth System, Max Planck Institute for Meteorology, Hamburg, Germany
Climate and Global Dynamics Division, National Center for Atmospheric Research, Boulder, CO 80307, USA
Cooperative Programs for the Advancement of Earth System Science, University Corporation for Atmospheric Research, Boulder, CO 80307, USA
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Using the largest ensemble of a climate model currently available, the Max Planck Institute Grand Ensemble (MPI-GE), we investigated the impact of the spatial distribution of volcanic aerosols on the El Niño–Southern Oscillation (ENSO) response. By selecting three eruptions with different aerosol distributions, we found that the shift of the Intertropical Convergence Zone (ITCZ) is the main driver of the ENSO response, while other mechanisms commonly invoked seem less important in our model.
Nicola Maher, Sebastian Milinski, and Ralf Ludwig
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Short summary
El Niño events occur as two broad types: eastern Pacific (EP) and central Pacific (CP). EP and CP events differ in strength, evolution, and in their impacts. In this study we create a new machine learning classifier to identify the two types of El Niño events using observed sea surface temperature data. We apply our new classifier to climate models and show that CP events are unlikely to change in frequency or strength under a warming climate, with model disagreement for EP events.
El Niño events occur as two broad types: eastern Pacific (EP) and central Pacific (CP). EP and...
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